I cannot see any error in my developer console.
Therefore, browser is not blocking your social icon fonts.

Please use the following troubleshooting steps.

1) To find out if this issue is caused by syntax errors in your custom css code.
Please copy all of them and keep in a text file as backup.
Remove them from your website and clear browser history before re-visiting to see if your icons are properly loaded.

2) Check for plugin conflict.
You can disable one plugin at a time, clear browser history and re-visit your website.

3) Update your theme and WordPress as well as all required plugins to latest available version.